Opioid formulations

Abstract

A depot precursor formulation comprising: a) a controlled-release matrix; b) at least oxygen containing organic solvent; c) at least 12% by weigh of at least one active agent selected from buprenorphine and salts thereof, calculated as buprenorphine free base. Corresponding depot compositions and methods of treatment in pain management, by opioid maintenance and related methods are provided.

The invention claimed is: 
     
       1. A method of treating opioid addiction in a patient, the method comprising administering to the patient a composition comprising:
 about 5% by weight of buprenorphine; 
 about 10% by weight of ethanol; 
 about 42% by weight of phosphatidylcholine; and 
 about 42% by weight of glycerol dioleate, 
 
       wherein the composition is administered once weekly from a pre-filled syringe, and 
       wherein the patient has previously received buprenorphine. 
     
     
       2. The method of  claim 1 , wherein the patient has previously received sublingual buprenorphine. 
     
     
       3. The method of  claim 1 , wherein the composition comprises about 3 to about 40 mg of buprenorphine (calculated as a free base). 
     
     
       4. The method of  claim 1 , wherein the composition, after contact with an aqueous fluid, forms a liquid crystalline phase structure. 
     
     
       5. The method of  claim 4 , wherein the liquid crystalline phase structure is a non-lamellar crystalline phase structure. 
     
     
       6. The method of  claim 1 , wherein, at steady state plasma concentrations, a Cmin and Cmax of buprenorphine in the patient is between about 0.4 ng/ml and 10 ng/ml after administration. 
     
     
       7. The method of  claim 1 , wherein a Cmin and Cmax of buprenorphine in the patient is between about 0.4 ng/ml and 10 ng/ml for at least a week after administration. 
     
     
       8. The method of  claim 1 , wherein the blood plasma concentration of buprenorphine in the patient is at least 0.2 ng/ml for at least a week after administration. 
     
     
       9. The method of  claim 1 , wherein the pre-filled syringe comprises a needle having a gauge greater than 20 G. 
     
     
       10. The method of  claim 1 , wherein the composition comprises:
 about 5.29% by weight of buprenorphine; 
 about 10% by weight of ethanol; 
 about 42.36% by weight of a phosphatidylcholine; and 
 about 42.36% by weight of glycerol dioleate.